Mixed AggregAtes: supramolecular organometallic species – AggregAte

Understanding the right association between the reactive species during a synthetic process, and more particularly during an enantioselective transformation, is fundamental when undertaking a rational design of effective and easy-to-handle synthetic tools. Such complexations have rarely been proved in solution since the concerned intermediates are often too fleeting to be easily characterized. Main cases of associations are in fact justified through X-ray diffraction analyses of solid states complexes, which are not necessarily representative of the solvated conditions. The will to carry out a concrete identification of key features and structural trends in solution brought us to gather three domains of competences that are the organic synthesis, spectroscopy (NMR) and theoretical chemistry. Our collaboration, which has yet proved its efficiency since ten years with about fifteen common publications, now aims at a new research program that will consist in examining in a sole class of organometallic reagents the ate complexes and the mixed aggregate. These two last domains, currently separated in two different categories, will be now regarded as a single field named the "Mixed AggregAte Chemistry" or MAAC. Our interest for this species will mainly focus on the possibility to transform the homo and hetero MAA's (Mixed AggregAtes) in efficient chiral inductors. In the frame of this application to the ANR, we want to initiate this new topic proposing to develop the two following aspects: - studying the chemistry of heterobimetallic heteroaggregates such as magnesiates, zincates, aluminates and titanates, and for which, one of the partners will be an (lithium, magnesium, calcium or other metal) amide. The reactivity of these MAA's will be tested in classical model reactions such as the deprotonation, 1,2- and 1,4- nucleophilic additions. These latters will then be good supports for enantioselectives applications in which the chirality will be brought by the amide of the MAA. - establishing a classification, in term of basicity and nucleophilicity, of a wide range of MAA's, in the perspective of furnishing a document of reference to chemists interested in using these classes of reactants. All these perspectives will be examined simultaneously and complementarily by the three research groups and with the help of one PhD student and two post-doctoral researchers. Meetings and discussion should be regularly schedulded since the three partners have yet shown their capacity to work efficiently together.